Nozzle for abrasives



May 8,, 1962 s. B. WILLIAMS NOZZLE FOR ABRASIVES Filed Oct. 1, 1959INVENTOR. SUMNER B. WILLIAMS BY ATTORNE Y United States Patent Office3,032,930 Patented May 8, 1962 3,032,930 NOZZLE FOR ABRASIVES Sumner B.Williams, 50 Deborah Road, Newton, Mass. Filed Oct. 1, 1959, Ser. No.843,781 2 Claims. (Cl. 51-11) This invention relates to a nozzle forapplying powdered abrasive. In particular, it relates to a sand blastingnozzle having more uniform flow and greatly improved wearingcharacteristics.

As the art of sand blasting has become more refined many industrial useshave arisen requiring sensitivity of control. Thus, for example, inpreparing the surface of a metal plate for use in lithography it isdesired to etch the surface with very small abrasive granules. The onlyarrangements that have been hitherto used or proposed for such purposeshave suffered from several deficiencies. One deficiency has been thedifficulty of obtaining true and stable alignment within the nozzlearrangement so as to get uniformity of flow and application. Also,abrasives often get through the washers and couplings required by somepreviously described nozzle arrangements. Another deficiency has beenthe rapid development of a terminal orifice eccentricity in the nozzlewhich is also partially due to the eccentric flow of the abrasive orlack of stable alignment. Since the surface treatment required forlithographic plates should be uniform and carefully controlled, the useof previously described nozzle arrangements has been costly and hasresulted in a substantial percentage of non-uniform plates.

One object of this invention is to provide a novel nozzle for abrasiveswhich will permit superior alignment and greater uniformity of flow.

A further object of this invention is to provide such a nozzle whichwill have more even wearing characteristics and thus a longer period ofuseful life.

Other objects and advantages of this invention will be apparent from thespecification and claims that follow and from the drawings of apreferred embodiment in which:

FIGURE 1 is a side view of the nozzle with a partial longitudinalsection together with a pipe and a hose in phantom.

FIGURE 2 is a rear end view of the nozzle alone.

FIGURE 3 is a front end view of the nozzle alone.

The objects of this invention are provided by a unitary nozzle having inconnected sequence and along a common axis, an internally threadedcylindrical tubular section adapted to receive the externally threadedpipe end of a hose, an internal frustro-conical tubular section Whosebase is co-extensive with the end of the threaded section and aninternal cylindrical tubular section extending from the frustro-conicalsection and terminating in a circular outer flow orifice. The nozzle ispreferably made in one piece from an abrasive-resistant material. Inproduction, the nozzle can be made by casting.

This type of nozzle provides true seating and alignment and permits theabrasive material to flow exclusively over a smooth uniform surface.There is no threaded path to divert the abrasive granules. Further, nowashers or couplings are required in the connection between pipe 17 andnozzle 11. In use, the wear of the conduits are uniform and avoid thecommon problem of eccentric wear known in the trade as key-holing" whichis the formation of a non-circular external flow orifice.

In the embodiment illustrated in the drawings, the nozzle 11 is shownwith the rear open cylindrical tubular section 12 having inner threading12A at the end which is the base of the frustro-conical tubular section13. At the tapering end of section 13 is a cylindrical tubular section14- terminating in outer flow orifice 15 wherein the flat end isperpendicular to the longitudinal axis of this series of tubulararrangements. A pipe such as 17 is threadable into the threaded section12 so that it seats up against the inner flow orifice 16. The sand blasthose 18 is attached to the other end of the pipe with a conventionalhose clasp 19. There is, thus, an uninterrupted smooth path for theabrasive granules between the end of the pipe and the outer orifice 15.

While the preferred embodiment of my invention has been described indetail, it will be understood that I do not wish to be limited to theparticular construction set forth, since various changes in the form,material, proportions and arrangement of parts, and in the details ofconstruction may be resorted to without departing from the spirit andscope of the invention, or destroying any of the advantages contained inthe same, heretofore described and defined in the following claims.

I claim:

1. In an abrasive-blasting apparatus of the type containing a hose, apipe connected to the hose and having terminal exterior threading and anozzle arrangement threadably secured to the pipe, a nozzle arrangementconsisting solely of a unitary member made from an abrasiveresistantmaterial and having in connected sequence and on a common longitudinalaxis, a rear, internally threaded cylindrical tubular section to receivesaid pipe, extended by a median section having an internalfrusto-conical bore of decreasing cross section, extended by aterminating section having a internal cylindrical tubular bore.

2. In an abrasive-blasting apparatus of the type containing a hose, apipe connected to the hose and having terminal exterior threading and anozzle arrangement threadably secured to the pipe, said nozzlearrangement consisting solely of a unitary member made from anabrasive-resistant material and having in connected sequence and on acommon longitudinal axis, a rear, internally threaded cylindricaltubular section to receive said pipe, extended by a median sectionhaving an internal frusto-conical bore having a decreasing crosssection, ex tended by a terminating section having an internal terminalcylindrical tubular bore, the base of said median regularfrustro-conical section being co-extensive with the end of said rearsection, the top of said threaded cylindrical section, the top of saidfrustro-conical section being co-extensive with the base of saidterminal cylindrical section, the interior surfaces of said bores ofsaid sections being smooth, uniform and continuous.

References Cited in the file of this patent UNITED STATES PATENTS561,483 Bryce June 2, 1896 FOREIGN PATENTS 131,161 Switzerland Apr. 1,1929 722,464 Great Britain I an. 26, 1955

